Add Polymorphic Memory Resource utilities and rework the separately compiled library:

- Dlmalloc's based C function are boost_cont_xxx no longer exported, but wrapped into C++ linkage dlmalloc_xxx functions to effectively reuse Boost's dynamic library and autolink machinery instead of rewriting machinery to compile the C source file.
- Refactored scoped_allocator_adaptor's construct logic as it was shared with polymorphic allocator's one. Moved common logic to detail/dispatch_uses_allocator.hpp. Refactored also scoped_allocator_adaptor test utilities to be reused with polymorphic_allocator tests.

test/memory_resource_logger.hpp

@@ -0,0 +1,86 @@
+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2015-2015. Distributed under the Boost
+// Software License, Version 1.0. (See accompanying file
+// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/container for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#ifndef BOOST_CONTAINER_TEST_MEMORY_RESOURCE_TESTER_HPP
+#define BOOST_CONTAINER_TEST_MEMORY_RESOURCE_TESTER_HPP
+
+#include <boost/container/pmr/memory_resource.hpp>
+#include <boost/container/vector.hpp>
+#include <cstdlib>
+
+class memory_resource_logger
+   : public boost::container::pmr::memory_resource
+{
+   public:
+   struct allocation_info
+   {
+      char *address;
+      std::size_t bytes;
+      std::size_t alignment;
+   };
+
+   boost::container::vector<allocation_info> m_info;
+   unsigned m_mismatches;
+
+   explicit memory_resource_logger()
+      : m_info()
+      , m_mismatches()
+   {}
+
+   virtual ~memory_resource_logger()
+   {  this->reset();  }
+
+   virtual void* do_allocate(std::size_t bytes, std::size_t alignment)
+   {
+      char *addr =(char*)std::malloc(bytes);
+      if(!addr){
+         throw std::bad_alloc();
+      }
+      allocation_info info;
+      info.address   = addr;
+      info.bytes     = bytes;
+      info.alignment = alignment;
+      m_info.push_back(info);
+      return addr;
+   }
+
+   virtual void do_deallocate(void* p, std::size_t bytes, std::size_t alignment)
+   {
+      std::size_t i = 0, max = m_info.size();
+      while(i != max && m_info[i].address != p){
+         ++i;
+      }
+      if(i == max){
+         ++m_mismatches;
+      }
+      else{
+         const allocation_info &info = m_info[i];
+         m_mismatches += info.bytes != bytes || info.alignment != alignment;
+         std::free(p);
+         m_info.erase(m_info.nth(i));
+      }
+   }
+
+   virtual bool do_is_equal(const boost::container::pmr::memory_resource& other) const BOOST_NOEXCEPT
+   {
+      return static_cast<const memory_resource *>(this) == &other;
+   }
+
+   void reset()
+   {
+      while(!m_info.empty()){
+         std::free(m_info.back().address);
+         m_info.pop_back();
+      }
+      m_mismatches = 0u;
+   }
+};
+
+#endif   //#ifndef BOOST_CONTAINER_TEST_MEMORY_RESOURCE_TESTER_HPP